1. Field of the Invention
This invention relates generally to handlebar-mounted cable controls for caliper-type bicycle brakes or other cable operated devices, and more particularly, to such a cable control mounted at the end of a handlebar for coaxial rotation thereabout.
2. Description of the Related Art
Handlebar-mounted bicycle caliper brake cable controls generally are provided in two basic configurations. The first employs a lever-type hand control whereby the rider, whose hands are positioned on the handlebar, must extend his fingers to grasp the lever and pull it towards the handlebar. The rider moves the lever, connected by a sheathed brake cable (Bowden cable) to the caliper brake, to overcome a spring-loaded biasing force which normally maintains the calipers in an open position, to clamp the brake shoes against the wheel rim to stop the bicycle.
This prior art configuration has several drawbacks, including the fact that in emergency situations, the rider must quickly move his hands to the correct position on the handlebar to activate the brake lever in time to stop the bicycle. If the rider's reaction is delayed, the brake levers may not be properly gripped, and the bicycle may not be stopped when desired.
A further drawback of the lever type brake control is that a certain amount of finger strength is required to exert sufficient force on the lever to obtain positive braking. Riders with relatively weak hands and fingers, such as children and the elderly, may have difficulty exerting sufficient force on lever type brake controls to obtain positive braking. Also, these two groups of riders often have inherently slower emergency reaction times, thus increasing the potential for accidents due to a failure to maintain proper brake control.
The second prior art type of handlebar-mounted brake cable control employs a hollow hand grip member axially rotatable about the ends of the handlebar. To activate the brakes, the rider twists the hand grip member, which is connected to the brake by a cable in a fashion similar to the lever type control described previously. The hand grip type of control obviates some of the drawbacks of the lever type control in that the omission of the lever removes the necessity to place the hands in as specific a location on the handlebar prior to braking. This decreases the emergency reaction time. In addition, the rider does not have to loosen his grip on the handlebar to activate the brakes. The rider merely rotates the grip by twisting his wrists, the muscles of which normally are stronger than the finger muscles. Thus, the hand grip type of brake control permits faster reaction time and requires less effort to operate.
Conventional rotatable hand grip brake cable controls have not been widely accepted. This is due in part to the relatively complex linkages and brackets normally found on such devices, which are also relatively expensive to manufacture, assemble and maintain compared to the lever type controls. Furthermore, in conventional rotatable hand grip controls, portions of the cable linkage related thereto are often mounted on the exterior of the handlebar, where they are exposed to damage, corrosion, and may cause injury to the rider, especially in emergency situations when the rider must move his hands quickly along the handlebar to the hand grip controls.
Additionally, prior art rotatable hand grip controls have several drawbacks. First, the spring-loaded biasing force which normally maintains the calipers in an open position is used to bias the rotatable handle member back into the non-braking position. Often, this force is insufficient to cause the handle grip to fully rotate back into the non-braking position. Thus, in some cases, the brakes may be left in a partially activated state after release.
Second, some prior art rotatable and grip controls rely on complementary angled surfaces to provide the pull on the cable when rotated relative to each other. In some cases, rough road conditions or rider inattention may cause the brake to engage inadvertently though unintentional hand or wrist movement. This occurs because the spring-loaded biasing force on the brakes which normally maintains the calipers in an open position is insufficient to counteract the force exerted by the inadvertent hand or wrist rotation.
Third, since the brake cable is directly attached to the handle grip member, failure of the brake cable in some situations may cause the handle grip member to detach from the handlebar. This may result in loss of control and injury to the rider.
It is therefore an object of the present invention to provide a bicycle brake control which is easily accessible in emergencies.
It is another object of the present invention to provide a bicycle brake control that requires relatively little force to activate yet is resistant to inadvertent hand and wrist rotations.
It is yet another object of the present invention to provide a bicycle brake control that easily returns to the non-braking position after release.
It is additionally an object of the present invention to provide a bicycle brake control which will not permit detachment of the handle member should the brake cable fail.
It is still a further object of the present invention to provide a bicycle brake control that is simple and inexpensive to manufacture and assemble and has a minimum of exposed components.